We cannot answer these questions, but they rise naturally from a consideration of Professor Hazen's volume. The first question which a reviewer has to put to himself is "What is the object of this book?" The object of Professor Hazen's is obvious: it is a text-book, a rapid survey of a period of history which, as he rightly says, possesses "a unity that is quite exceptional among the so-called 'periods' of history." As a text-book it has great merits; it is accurate and brief, it runs with great rapidity through all the more important facts of its "period," and the author's opinions and prejudices are severely repressed. It has some obvious faults: the author seems to us ill-advised to have added his last chapter in the form and size adopted by him. This chapter deals with the actual events of the world war, and occupies nearly a quarter of the entire book. This throws the whole of his book out of shape. The war in itself had, of course, enormous importance, but the details of its progress are of little importance in a survey like this. In the previous pages we have been whirled from the Balkan question to the Irish, from the Irish question to the rise of Japan, from the rise of Japan to the Russian internal struggle, and many of these immense complicated problems have necessarily been dismissed in a few pages. There is no room in a book on this scale for a description of the campaigns of the war, and Professor Hazen's volume loses rather than gains by his attempt to deal with them. But as a text-book it has merits above the average. One great merit is inherent in it--it looks at history not from a national but a European or world angle. We are inclined to believe that for use in schools no histories of "France," "England," or other individual countries should be tolerated, that all history should be either of Europe, Asia, of some continent or era, or of the world. And then, perhaps, historians might be able to deal a little more with the good that men do communally than with the evil. THE TANK CORPS. By MAJOR CLOUGH WILLIAMS-ELLIS, M.C., and A. WILLIAMS-ELLIS. With an Introduction by MAJOR-GENERAL H. J. ELLES, C.B., D.S.O. _Country Life._ 10_s._ 6_d._ net.